The present invention relates to a footwear insole and method of manufacture therefor. In particular, the invention relates to an insole formed of a sheet material having an opening therein and a soft, flexible comfort and support pad integrally molded in the opening. According to the method, a precut insole board having an opening is located in a mold having a cavity in registration with the opening. The cavity is filled to a selected level, and the mold is closed for a timed curing step.
Removable footwear inserts which sit atop the insole are known. Such inserts generally have one or more cushioned areas which provide comfort and relieve pressure on the foot. A known insert has a resilient member glued in an aperture therein. Another insole is formed with a removable portion adapted to receive a resilient member therein.
While the known support devices may be incorporated in conventional footwear without major structural or aesthetic problems, it is difficult to incorporate a comfortable, stylish and structurally sound support device in certain types of ultra-thin footwear. For example, the widely popular "d ecolt e" style of women's footwear is particularly thin and covers only a small part of the foot. Thus, it is difficult to provide a cushioned insole which is sufficiently strong and flexible without interfering with the aesthetic features of the style.
In the d ecolt e shoe, for example, the upper part of the shoe is reduced to a minimum and does not cover most of the foot except around the margins of the shoe. The addition of a support and cushion results in added thickness to the shoe structure and thus results in an increase in the height of the upper. Thus, an enlargement to the footwear volume becomes necessary, which enlargement is aesthetically undesirable. Similar problems also exist with respect to certain styles of men's footwear, which have a rather thin slender shape and in which it is undesirable to increase the external footwear volume.
There is presently no practical method for manufacturing a soft, flexible and sufficiently supportive element for such footwear, and which also has structural integrity. Likewise, no methods have been provided to form a shoe having an insole which incorporates such a soft, supportive, flexible and structurally integral material without unduly increasing the thickness of the insole or without the need for a supplemental insert.
It is an object of the present invention to overcome the problems of the prior art and to provide a method for manufacturing a structurally sound insole having relatively little overall thickness yet providing cushioning, flexibility and sufficient foot support.
It is also an object of the invention to provide a method for manufacturing an insole having areas of flexibility and softness and which may be employed in any insole for any model of shoe, including the ultra-thin, elegant popular styles.